Oscillating grinder



May 15, 1934. LE -r 1,959,103

OSCILLATING GRINDER Filed May 5, 1952 ATTORNEY.

3 J 60 if INVENTOR. a? y GEamsa fl LET/m m Patented May 15, 1934 UNITE TATE PAT if? 6 Claims.

My invention relates to a new and useful improvement in an oscillating grinder adapted for use on filing and grinding machines generally and particularly adapted for use in grinding die sections, trueing up die sections after heat treating and so forth. It is an object of the present invention to provide in a grinding machine of this class a structure whereby, simultaneously, a rotary and reciprocating movement may be im parted to a grinding member.

Another object of the invention is a provision of an electric motor having an armature movable axially of its iield.

Another object of the invention is the provision with an electric motor for armature movable axially of its field of mechanism for reciprocating the armature relatively to its field.

Another object of the invention is the provision in combination with an electric motor having an armature movable axially of its field of mechanism for reciprocating the armature relatively to its field.

Another object of the invention is the provision in combination with an electric motor having an armature movable axially of its field is a cam actuated mechanism which will serve to move the armature axially of its field in one direction.

Another object of the invention is the provision of a device of this class which will be simple in structure, economical of manufacture, durable, and highly efiicient in use. I

Other objects will appear hereinafter.

The invention consists in the combination and arrangement of parts hereinafter described and claimed.

The invention will be best understood by a ref erence to the accompanying drawing which forms a part of this specification, and in which,

Fig. 1 is a central vertical sectional view of the invention.

Fig. 2 is a fragmentary view taken on line 2-2 of Fig. l.

The invention is used with the type of grinding machine which is disclosed in my case pending application, Serial No. 594,497. In this type of grinding machine a supporting standard 7 is provided with pulleys 8 and 9 around which extends a cable 10 for moving vertically the supporting standards 11 on which is positioned the bed 51. The central portion 12 on the standard 7 serves to support a motor housing which comprises the base section 13, the middle section 14, and the top section 15. The field coils 16 are positioned within the housing and the armature 17 is provided with the shaft 18. Formed centrally in the bottom section 13 is an opening 19 in which is secured by a press fit, the bushing 29 having on its lower end the inwardly projecting flange 21. Slidable within the bushing 20 is a cup shaped bushing 22 in which is positioned a bearing comprising the rings 23 and 25, and the roller bearings 24 to form a bearing for the reduced end 26 of the shaft 18. This shaft 18 projects through a bearing 27 above the plate 28. An axially extending groove 29 is formed in the periphery of the bushing 22, and projecting into this groove is a pin or stud 30 which is secured to and projects inwardly from the fixed bushing 20.

A central opening 31 is formed in the top 15 of the motor housing and pressed into the opening 31 is a bushing 32 having a base 33 secured thereto through which the shaft 18 projects. This base 33 is provided with a groove 34 in which a suitable lubricant or packing may be positioned. A reduced portion 36 of the shaft is embraced by the bearing consisting of the rings 37 and 38 and the roller bearing 39 which are positioned within the bushing 40 which is loosely positioned in the bushing 32. An axially extending peripheral groove 41 is formed in the bushing 40 and a pin 42 projecting inwardly from the bushing 32 engages in this groove. A cover 43 is provided for the opening 41 for the top 15. This cover is provided with a recess 44 against which engages the spring 45 which embraces the shaft, and the opposite end of this spring engages against a collar 46 extending inwardly from the bushing 40. A reduced portion 47 of the shaft 18 projects through the cover 43 and carries a chuck 48 by means of which a suitable grinding member 49 may be attached thereto, this grinding member 49 extending through an opening 50 formed in the bed 51.

Supported on a suitable bracket 52 adjacent the standard '7 is an electric motor 53, the shaft 54 of which is connected through a suitable gear housing 55 with the shaft 56. This shaft 56 is connected by the flexible coupling 57 to the shaft 58 which is j ournaled in the bushing 59 and on which is fixedly mounted the cam 60. This cam is adapted to engage the bottom of a cup shaped bushing 22.

There are, of course, suitable switches provided for the center of both motors. In operation, when the motor within the housing, formed from the sections 13, 14, and 15, is running the shaft 18 will be rotated, thus efiecting a rotation of the grinding element 49. The bearings in the bushings 22 and 40 are fixed in these bushings so that axial movement thereof in the bushings is prevented. When the motor 53 is running and the shaft 58 is rotated the armature 1'? will be reciprocated axially. The cam 60 forcing through its engagement with the bushing 22, and upward movement of the bushing 22 which will carry with it the shaft 18 and the armature 17. This movement will force the bushing 40 to move upwardly against the compression of the spring 45. As the lobe of the cam returns an engagement with the bushing 22, the spring 45 will return the armature to its normal position, thus forcing the bushings 40 and 22 downwardly totheir normal positions. This reciprocating of the armature will not interfere with the rotation of the armature as the field must be sufliciently long to permit the axial movement without interference with the rotary movement. By rotating the cam 60 to any desired position the grinding element may be raised or lowered to any desired position within its range of limits without interfering with the rotation thereof.

I have thus provided in a grinding machine of this class a structure whereby the grinding or filing operation on the work piece may be effected through a rotary action and at the same time by an axial movement of the grinding or filing element. This eliminates the appearance of any grain structure on the work piece which results from the contact of the grinding or filing element therewith and affords a smoother surface than can be obtained, wherein but a single movement is imparted to the grinding or filing element. This also eliminates the necessity of moving the work piece in order that certain parts may be reached by the grinding or filing element. This structure also, because of subjecting the grinding or filing member to use throughout its entire length extends a maximum use from the grinding or filing element.

It will also be noted that I have provided a means whereby the armature of an electric motor may be reciprocated axially, while it is being rotated and whereby the armature may be easily and quickly moved to various axial positions relatively to its field without interfering with the rotation of the armature.

While I have illustrated and described the preferred form of construction, I do not wish to limit myself to the precise details of structure shown but desire to avail myself of such variation and modification as come within the scope of the appended claims.

Having thus described my invention what I claim as new and desire to secure by Letters Pat- I ent:

1. In a grinding machine of the class described, an electric motor; an armature in said motor; a shaft projecting through said armature and supporting the same; bearings for supporting said shaft at opposite sides of said armature; and a bearing retainer at each side of said armature for retaining said bearings, said bearing retainers being axially movable.

2. In a grinding machine of the class described, an electric motor; an armature in said motor; a shaft projecting through said armature and supporting the same; bearings for supporting said shaft at opposite sides of said armature; a bearing retainer at each side of said armature for retaining said bearings, said bearing retainers being axially movable; and cam means for moving said bearing retainers axially in one direction.

3. In a grinding machine of the class described, an electric motor; an armature in said motor; a shaft projecting through said armature and supporting the same; bearings for supporting said shaft at opposite sides of said armature; a bearing retainer at each side of said armature for retaining said bearings, said bearing retainers being axially movable; cam means for moving said bearing retainers axially in one direction; and resilient means for moving said bearing retainers axially in the opposite direction.

4. In a grinding machine of the class described, an electric motor; an armature in said motor; a shaft projecting through said armature and supporting the same; and bearings for supporting said shaft at opposite sides of said armature, said bearings being axially movable with the axial movement of said shaft.

5. In a grinding machine of the class described, an electric motor; an armature in said motor; a shaft projecting through said armature and supporting the same; bearings for supporting said shaft at opposite sides of said armature, said bearings being axially movable with the axial movement of said shaft; and cam means for effecting the axial movement of said shaft.

6. In a grinding machine of the class described, an electric motor; an armature in said motor; a shaft projecting through said armature and supporting the same; bearings at opposite sides of said armature for supporting said shaft; means for mounting said bearings for permitting axial movement of the same upon axial movement of said shaft; and means for effecting axial movement of said shaft.

GEORGE M. LE TARTE. 

